1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2023 SUSE LLC Andrea Cervesato <andrea.cervesato@suse.com>
4 */
5
6/*\
7 * [Description]
8 *
9 * Verify that EPOLLONESHOT is correctly handled by epoll_wait.
10 * We open a channel, write in it two times and verify that EPOLLIN has been
11 * received only once.
12 */
13
14#include <poll.h>
15#include <sys/epoll.h>
16#include "tst_test.h"
17#include "tst_epoll.h"
18
19static int fds[2];
20static int epfd;
21
22static void cleanup(void)
23{
24	if (epfd > 0)
25		SAFE_CLOSE(epfd);
26
27	if (fds[0] > 0)
28		SAFE_CLOSE(fds[0]);
29
30	if (fds[1] > 0)
31		SAFE_CLOSE(fds[1]);
32}
33
34static void run(void)
35{
36	struct epoll_event evt_receive;
37	char buff = 'a';
38
39	SAFE_PIPE(fds);
40
41	tst_res(TINFO, "Polling on channel with EPOLLONESHOT");
42
43	epfd = SAFE_EPOLL_CREATE1(0);
44
45	SAFE_EPOLL_CTL(epfd, EPOLL_CTL_ADD, fds[0], &((struct epoll_event) {
46		.events = EPOLLIN | EPOLLONESHOT,
47		.data.fd = fds[0],
48	}));
49
50	tst_res(TINFO, "Write channel for the 1st time. EPOLLIN expected");
51
52	SAFE_WRITE(0, fds[1], &buff, 1);
53	TST_EXP_EQ_LI(SAFE_EPOLL_WAIT(epfd, &evt_receive, 10, 0), 1);
54	TST_EXP_EQ_LI(evt_receive.events & EPOLLIN, EPOLLIN);
55	TST_EXP_EQ_LI(evt_receive.data.fd, fds[0]);
56
57	SAFE_READ(1, fds[0], &buff, 1);
58	TST_EXP_EQ_LI(SAFE_EPOLL_WAIT(epfd, &evt_receive, 10, 0), 0);
59
60	tst_res(TINFO, "Write channel for the 2nd time. No events expected");
61
62	SAFE_WRITE(0, fds[1], &buff, 1);
63	TST_EXP_EQ_LI(SAFE_EPOLL_WAIT(epfd, &evt_receive, 10, 0), 0);
64
65	SAFE_CLOSE(epfd);
66	SAFE_CLOSE(fds[0]);
67	SAFE_CLOSE(fds[1]);
68}
69
70static struct tst_test test = {
71	.cleanup = cleanup,
72	.test_all = run,
73};
74